Consider COPD, and perform spirometry, if any of these indicators are present in an individual over age 40.
- Presence of multiple key indicators increases the probability of a true diagnosis of COPD.
- Spirometry is needed to establish a diagnosis of COPD.

Key Indicators
Dyspnea	Progressive (worsens over time) Usually worse with exercise Persistent (present every day) Described by the patient as an “increased effort to breathe,” “heaviness,” “air hunger,” or “gasping.”
Chronic cough	May be intermittent and may be unproductive
Chronic sputum production	Any pattern of chronic sputum production may indicate COPD
History of exposure to risk factors	Tobacco smoke Occupational dusts and chemicals Smoke from home cooking and heating fuels

Differential Diagnosis

Diagnosis	Suggestive features (but not always present)
COPD	Onset in mid-life (onset in younger adults, consider A1AT deficiency) Symptoms slowly progressive. Long history of tobacco smoking. Dyspnea during exercise. Largely irreversible airflow limitation.
Asthma	Onset early in life (often childhood). Symptoms vary from day to day. Symptoms at night/early morning. Allergy, rhinitis, and/or eczema also present. Family history of asthma. Largely reversible airflow limitation.
CHF	Fine basilar crackles on auscultation. Chest X-ray shows dilated heart, pulmonary edema. Pulmonary function tests indicate volume restriction, not airflow limitation.
Bronchiectasis	Large volumes of purulent sputum. Commonly associated with bacterial infection. Coarse crackles/clubbing on auscultation. Chest X-ray/CT shows bronchial dilation, bronchial wall thickening.
TB	Onset all ages Chest X-ray shows lung infiltrate. Microbiological confirmation. High local prevalence of tuberculosis.
Obliterative bronchiolitis	Onset in younger age, nonsmokers. May have history of rheumatoid arthritis or fume exposure. CT on expiration shows hypodense areas.
Diffuse panbronchiolitis	Most patients are male and nonsmokers. Almost all have chronic sinusitis. Chest X-ray and HRCT show diffuse small centrilobular nodular opacities and hyperinflation.